In electronics, a digital-to-analog converter (DAC) is a device that converts a digital signal into an analog signal. DACs may be widely used in numerous applications and may, for example, be implemented as high speed converters suitable for use in telecommunication systems.
Multi-bit DACs (i.e., DACs with greater than two potential output values) may include a plurality of current sources that are controlled by a digital input signal and drive a transimpedance amplifier in order to generate an analog voltage output. The accuracy of a DAC may depend on the accuracy of the individual current sources. Similarly, the linearity of a DAC may depend on how well the individual current sources match each other. To improve the accuracy and/or the linearity of a DAC, the DAC's current sources may be continuously calibrated during operation of the DAC.